From patchwork Mon Jan 21 21:57:21 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tilman Schmidt X-Patchwork-Id: 214289 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id A121D2C0079 for ; Tue, 22 Jan 2013 09:30:51 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752301Ab3AUW0h (ORCPT ); Mon, 21 Jan 2013 17:26:37 -0500 Received: from gimli.pxnet.com ([89.1.7.7]:45315 "EHLO mail.pxnet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751625Ab3AUW0g (ORCPT ); Mon, 21 Jan 2013 17:26:36 -0500 X-Greylist: delayed 1730 seconds by postgrey-1.27 at vger.kernel.org; Mon, 21 Jan 2013 17:26:35 EST Received: from xenon.ts.pxnet.com (p5DE8DB81.dip.t-dialin.net [93.232.219.129]) (user=ts author=<> mech=DIGEST-MD5 bits=0) by mail.pxnet.com (8.13.8/8.13.8) with ESMTP id r0LLvQoW025460 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Mon, 21 Jan 2013 22:57:29 +0100 Received: by xenon.ts.pxnet.com (Postfix, from userid 1000) id 8D8CB1400D4; Mon, 21 Jan 2013 22:57:21 +0100 (CET) From: Tilman Schmidt To: Karsten Keil , David Miller CC: Hansjoerg Lipp , Karsten Keil , i4ldeveloper@listserv.isdn4linux.de, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Message-ID: <20130121-patch-isdn-06.tilman@imap.cc> In-Reply-To: <20130121-patch-isdn-00.tilman@imap.cc> References: <20130121-patch-isdn-00.tilman@imap.cc> Subject: [PATCH 6/6] isdn/gigaset: fix zero size border case in debug dump Date: Mon, 21 Jan 2013 22:57:21 +0100 (CET) X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (mail.pxnet.com [89.1.7.7]); Mon, 21 Jan 2013 22:57:29 +0100 (CET) X-Scanned-By: MIMEDefang 2.70 on 89.1.7.7 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org If subtracting 12 from l leaves zero we'd do a zero size allocation, leading to an oops later when we try to set the NUL terminator. Reported-by: Dan Carpenter Signed-off-by: Tilman Schmidt CC: stable --- drivers/isdn/gigaset/capi.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/drivers/isdn/gigaset/capi.c b/drivers/isdn/gigaset/capi.c index 68452b7..03a0a01 100644 --- a/drivers/isdn/gigaset/capi.c +++ b/drivers/isdn/gigaset/capi.c @@ -248,6 +248,8 @@ static inline void dump_rawmsg(enum debuglevel level, const char *tag, CAPIMSG_APPID(data), CAPIMSG_MSGID(data), l, CAPIMSG_CONTROL(data)); l -= 12; + if (l <= 0) + return; dbgline = kmalloc(3 * l, GFP_ATOMIC); if (!dbgline) return;